When dpkg install a package, when popularity-contest work, when I copy a file on Hard Disk, I can't use my computer, all interfaces are freeze

[Stéphane Klein]

Hi,

I've write to you because when my system have many access to Hard Disk, 
I can't use my computer.

When dpkg install a package, when poplarity-contest is executed I can do 
nothing, worse sometime I can move the mouse cursor !

I use Ubuntu 11.04 on MacBook3,1 (120Go at 5400 rpm).

What can I do to fix this issue ?

Regards,
Stephane
-- 
Stéphane Klein <stephane at harobed.org>
blog: http://stephane-klein.info
Twitter: http://twitter.com/klein_stephane
pro: http://www.is-webdesign.com